The speed of the blue Plexicushion courts has sparked debate this year, with some players adamant they have picked up in pace, while tournament director Craig Tiley says they were re-laid with exactly the same surface as previous years.

The prospect of slick courts, made even faster by baking heat forecast for the first week at MelbournePark, has been welcomed by some players, including Roger Federer and Australian Lleyton Hewitt, but Spaniard Nadal made his displeasure clear.

"Completely different conditions than what I remembered of this tournament," the 27-year-old told reporters on Saturday of his training on the courts.

"Faster conditions that I ever played here in Australia.

"Well, I really don't understand very well why they change because the last couple of years, Australian Open had amazing matches, long ones, good ones for the crowd.

"I don't know why the people who decide to make the conditions that fast.

"I am not sure for the show that it's the best thing. But they decide and I'm just a player to try to be competitive from the beginning.

"I arrived one week before. I think that I am practising better a little bit every day. I hope to adjust my game to these conditions."

Nadal has thrived on slower surfaces, winning eight of his 13 grand slam titles on the clay courts of Roland Garros, but only one at the Australian Open in 2009.

Barring 2012, when he participated in a record five hour, 53 minute marathon final against winner Novak Djokovic, Nadal has been dogged by injuries in recent years and was forced to miss last year's tournament due to an illness which stalled his comeback from a serious knee injury.

Nadal's eventual return in 2013, when he captured the French and U.S. Opens among 10 titles, was little short of astonishing, and he arrives in MelbournePark top seed and the main threat to Djokovic's hopes of a fourth straight Australian Open crown.

His recapturing of the world number one spot saw Djokovic promptly contact Boris Becker to become the Serb's new head coach alongside long-serving Marian Vajda, but Nadal said he cared little for the ranking.

"(The) most important thing for me is be able to be competitive in every tournament that I going to play," he said.

"When you are getting older, thinking about the number one ranking is tougher.

"You have to take care a little bit more about your body, your health. For me the main goal is to try to be here for a long time, for not only one more or two more years.

"If that makes me lose maybe some tournaments to protect my health, (the) consequence will (be) less chances to be in the top position of the rankings.

"I have been in the top two positions in the rankings for a lot of my career, so is not something that is a priority today."

Nadal will play 52nd-ranked Australian Bernard Tomic in the first round, a match certain to be held on the centre court in Rod Laver Arena and in the prime-time evening session.

The Mallorcan swatted aside a teenage Tomic in the 2011 tournament but may not have it quite so easy in the rematch against the rangy 21-year-old, who plays his best tennis in front of home fans and has warmed up by reaching the final of the Sydney International.

Nadal has never been anything less than popular Down Under, but targeted local fans with a charm offensive ahead of the clash.

"Australian crowd is one of the best," he said. "I really have fun all the time when I was able to play on this fabulous court, Rod Laver Arena.

"I think they understand about tennis. They respect always the opponent. I am not worried about that. I'm sure the crowd will be great."